Flexible chain implants and instrumentation

Abstract

A flexible chain implant for insertion into an interior volume of a vertebral body. The implant may be implanted in an insertion position for sliding through a cannula and is flexible for packing into the interior volume in an implanted configuration. The implant randomly separates in the implanted configuration. The implant includes a top member and a bottom member, wherein the top and bottom members are coupled to one another at a coupled portion. The top and bottom members preferably each include an inner surface such that the inner surfaces include a plurality of alternating projections and recesses so that the projections are received within the recesses in an insertion position. Alternatively, the implant may include a plurality of substantially non-flexible bodies and a plurality of substantially flexible links interconnecting the bodies. The non-flexible bodies include a plurality of facets and/or abutment surfaces.

What is claimed is: 
     
       1. A flexible chain implant configured to be inserted into an interior volume formed in a bone, the implant comprising:
 a top member having an outer surface and an inner surface; and 
 a bottom member having an outer surface and an inner surface; the top and bottom members being coupled to one another, wherein the top and bottom members being constructed of bone, each of the inner surfaces of the top and bottom members include a plurality of alternating projections and recesses, and the projections of the top member are received within the recesses of the bottom member, the projections of the bottom member are received within the recesses of the top member, and 
 the implant defines a first end and an opposed second terminal end, and the top and bottom members are coupled together at the first end when the implant is in an insertion position and an implanted configuration, and the top and bottom members are configured to separate from one another when in the implanted configuration. 
 
     
     
       2. The implant of  claim 1 , wherein the top and bottom members are formed of a monolithic portion of bone. 
     
     
       3. The implant of  claim 1 , wherein the top member is connected to the bottom member at the coupled portion. 
     
     
       4. The implant of  claim 1 , wherein the top and bottom members are coupled together at the coupled portion via a dovetail joint. 
     
     
       5. The implant of  claim 4 , wherein the top and bottom members are fixed together at the coupled portion by a demineralized dovetail joint. 
     
     
       6. The implant of  claim 1 , wherein the top and bottom members are fixed together at the coupled portion by a demineralized coupled portion. 
     
     
       7. The implant of  claim 1 , further comprising:
 a cap having an engagement recess, the top member includes a first engagement projection at the coupled portion, the bottom member includes a second engagement projection at the coupled portion, the first and second engagement projections received within the engagement recess at the coupled portion in an assembled configuration, the cap configured to secure the top member to the bottom member in the assembled configuration. 
 
     
     
       8. The implant of  claim 1 , further comprising: a pin that couples the top and bottom members together at the coupled portion in an assembled configuration. 
     
     
       9. The implant of  claim 8 , wherein the top member includes a top engagement portion and the bottom member includes a bottom engagement portion, the top engagement portion having a top aperture and the bottom engagement portion having a bottom aperture, the top and bottom apertures receiving the pin in the assembled configuration. 
     
     
       10. The implant of  claim 9 , wherein the top member includes a stopper projection at the top engagement portion to prevent inadvertent removal of the pin in the assembled configuration. 
     
     
       11. The implant of  claim 1 , wherein the top member includes a longitudinal projection and the bottom member includes a longitudinal channel, the longitudinal projection received in the longitudinal channel in an assembled configuration. 
     
     
       12. The implant of  claim 11 , wherein the longitudinal projection is one of snap-fitted and slidably received into the longitudinal channel.